From 3f977758f62a7ac95b41757c81eb7dad294e40d2 Mon Sep 17 00:00:00 2001
From: Moritz Heidkamp <moritz.heidkamp@bevuta.com>
Date: Tue, 7 Nov 2023 16:47:03 +0100
Subject: [PATCH] Preserve ex-data of all ex-info exceptions in the cause chain
 (#61)

Instead of only adding ex-data of the top-level exception into the extra map, walk down the cause
chain and add all ex-data encountered therein. To prevent them from clobbering each other or any
keys already present in the extra map, nest all ex-data under separate keys. The top-level
exception's ex-data is added under "ex-data" while causes are added under "ex-data, cause <n>:
<message>" where `<n>` is the cause's position in the chain and `<message>` is its message.
---
 src/sentry_clj/core.clj       | 21 ++++++++++++++++++++-
 test/sentry_clj/core_test.clj | 13 +++++++++++--
 2 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/src/sentry_clj/core.clj b/src/sentry_clj/core.clj
index dc89900..d67e311 100644
--- a/src/sentry_clj/core.clj
+++ b/src/sentry_clj/core.clj
@@ -90,6 +90,25 @@
       (.setOthers request (java-util-hashmappify-vals other)))
     request))
 
+(defn ^:private merge-all-ex-data
+  "Merges ex-data of all ex-info exceptions in the cause chain of exn into extra.
+  Each ex-data is added under a separate key so that they don't clobber each other."
+  [extra exn]
+  (loop [exn exn
+         num 0
+         extra extra]
+    (if exn
+      (let [data (ex-data exn)]
+        (recur (ex-cause exn)
+               (inc num)
+               (cond-> extra
+                 data
+                 (assoc (if (zero? num)
+                          "ex-data"
+                          (str "ex-data, cause " num ": " (ex-message exn)))
+                        data))))
+      extra)))
+
 (defn ^:private map->event
   "Converts a map into an event."
   ^SentryEvent
@@ -130,7 +149,7 @@
         (.addBreadcrumb sentry-event ^Breadcrumb breadcrumb)))
     (when server-name
       (.setServerName sentry-event server-name))
-    (when-let [data (merge extra (ex-data throwable))]
+    (when-let [data (merge-all-ex-data extra throwable)]
       (doseq [[k v] (java-util-hashmappify-vals data)]
         (.setExtra sentry-event k v)))
     (when throwable
diff --git a/test/sentry_clj/core_test.clj b/test/sentry_clj/core_test.clj
index 942be28..6cc6887 100644
--- a/test/sentry_clj/core_test.clj
+++ b/test/sentry_clj/core_test.clj
@@ -206,7 +206,14 @@
 (defexpect map->event-test-with-ex-info
   (expecting
    "an ex-info event"
-   (let [output (serialize (assoc event :throwable (ex-info "bad stuff" {:ex-info 2})))
+   (let [output (serialize (assoc event :throwable (ex-info "bad stuff"
+                                                            {:data 1}
+                                                            (ex-info "this is a transitive cause"
+                                                                     {:data 2}
+                                                                     (RuntimeException.
+                                                                      "this is a non-info transitive cause"
+                                                                      (ex-info "this is the root cause"
+                                                                               {:data 3}))))))
          actual (strip-timestamp output)]
      (expect {"release"     "v1.0.0"
               "event_id"    "4c4fbea957a74c99808d2284306e6c98"
@@ -232,7 +239,9 @@
                              "url" "http://example.com"}
               "transaction" "456"
               "extra"       {"one" {"two" 2}
-                             "ex-info" 2}
+                             "ex-data" {"data" 1}
+                             "ex-data, cause 1: this is a transitive cause" {"data" 2}
+                             "ex-data, cause 3: this is the root cause" {"data" 3}}
               "platform"    "clojure"
               "contexts"    {}
               "breadcrumbs" [{"type"      "http"